The present invention relates to a process for preparing a powdered ice cream product which can be re-constituted in cold water. The powdered ice cream product is high in fat and high in sugar.
Instant or dry powdered milk products have been widely manufactured and sold throughout the world. Some of these are fat-containing dry milk products and other are skim milk products. They may be unflavored or flavored such as instant hot or cold chocolate powdered mixes.
One example of an instant fat-containing dry milk is illustrated in U.S. Pat. No. 4,318,932. This patent discloses a process for manufacturing an instant dry milk in which non-fat milk powder is used as a source material and fat is added in the instantizing or agglomerating operation. The process addresses the problem of having an instant milk which is easily re-constituted and has good disbursability in cold water while not suffering from the problem of cream separation. However, this process does not address the problems of a powdered ice cream which requires not only a high fat content but a high sugar content.
U.S. Pat. No. 3,956,521 discloses a process for producing powder from milk using a spray-dried process to produce a powder which is further dried in a fluidized bed. The second drying process is required in order to produce the low humidity, low moisture content powder which is required in such applications.
The preparation of a powdered skim milk additive is disclosed in U.S. Pat. No. 4,096,287 in which an additive is prepared which when added to skim milk makes the resultant mixture taste and look more like whole milk.
As can be seen by reading the prior patents, the problems inherent in producing a powdered ice cream with good water solubility have not been addressed. Most of the prior art has dealt with the problems inherent in manufacturing a powdered skim milk or powdered whole milk product. However, when manufacturing a powdered ice cream product, different problems arise. For example, one must deal with not only the high fat content of the powder but also the high sugar content of the powder. Also, the finished powder must have a very low moisture content in the range of 1.2%-1.5% to facilitate good flow properties of the powder. The powder must re-constitute easily and completely and the individual components cannot separate.
Thus, it is an object to provide a powdered ice cream product that can be stored and shipped without the need for refrigerated containers or transport means.
It is another object of the invention to provide a process for the preparation of a powdered ice cream product having a high fat and high sugar content yet retain good flavor and physical appearance characteristics. A related object is the object of providing a process for the preparation of a powdered ice cream product which is low in its final moisture content which prevents the powder from melting and sticking to itself or the containers in which the powder is manufactured and transported.
Another object is to provide a powdered ice cream product which can be easily and completely re-constituted with water. Yet another object is the object of providing a process which provides a homogenous powdered ice cream in which the sugars, milk solids or fats do not separate when re-constituted. Related to this object is the object of providing a homogenous powdered ice cream in which the components are homogeneously distributed throughout the powder in their correct percentages.
Another object is the object of providing a process for the preparation of a powdered ice cream product which is relatively economical in its manufacture and provides for a single stage, spray-drying process to manufacture the powder.
The inventive process comprises first preparing a liquid ice cream mix by mixing milk solids, cream, sugar and a stabilizer/emulsifier. Flavoring may be added at this step. The mix at this point contains approximately 40.5% total solids consisting of approximately 15% fat, 16% sugar, 9% milk solids--non-fat and 1/2% stabilizer/emulsifier.
The mixture is then pasteurized at approximately 180.degree. F. for 22.5 seconds via the high temperature short time process. It is then homogenized at approximately 2800 psi. The mixture is then immediately cooled to 40.degree.-42.degree. F. and held at this temperature for 3-4 hours. The mixture is then pre-heated to approximately 160.degree. F. and pumped to a single-stage spray-drying chamber by means of a high pressure pump at approximately 2500 psi. The mixture is atomized through a series of rotating head pressure nozzles. As the atomized mixture enters the drying chamber, it is formed into powder particles through contact with the hot air. The moisture content is maintained at 1.2%-1.5%. In order to re-constitute the powder, it is only necessary to mix it with the proper amount of water to re-constitute a mixture identical to that which was spray-dried. The mixture is then frozen in an ice cream maker with the resultant ice cream having improved flavor and physical appearance characteristics as compared to powdered ice cream formed by other processes.
These and other objects and advantages of the invention will become apparent upon reading the detailed description of the preferred embodiment .